Needle electrodes are designed for use in neurological examinations using electronic monitoring equipment, namely electromyograph (EMG) equipment. The needle electrodes are connected to monitoring equipment and then inserted into a patient's muscle at the location that is to be stimulated or probed. As a needle electrode is inserted into a patient's body, both the electrode and operator may be exposed to bodily fluids carrying infectious diseases. Because of the danger associated with exposure to bodily fluids, the Food and Drug Administration (FDA) has stringent requirements regarding packaging, sterilization, reuse, disposal and testing performed using needle electrodes.
FDA requirements have resulted in two basic types of needle electrodes being used in the marketplace. The first type of needle electrode generally used is a disposable electrode assembly including needle electrode, lead wires, and electrical connectors all joined to form a single unit. The electrode assemblies are generally sterilized and prepackaged for a one-time use by a physician. The physician opens the sterilized package, connects the needle electrode to the appropriate monitoring equipment, and inserts the needle electrode into a patient's muscle. After completing testing, the entire electrode assembly is disconnected from the monitoring equipment and discarded.
Disposable needle electrode assemblies are fairly expensive and highly wasteful of resources due to their one-time use. Disposable electrode assemblies also add to the quantity of medical waste produced, increasing waste disposal costs. Because specific users require various length and diameter disposable needle electrode assemblies, users must stock large numbers of expensive needle electrode assemblies, adding to inventory overhead and storage costs.
The second type of needle electrode assembly commonly available is a reusable needle electrode assembly designed to be sterilized after each use. Similar to disposable assemblies, reusable needle electrode assemblies are generally manufactured as single piece units including electrical connectors, leads, and needle electrodes. Reusable needle electrode assemblies are not as wasteful of resources; however, they are expensive and time-consuming to use due to the procedures necessary to sterilize the needle electrode assemblies prior to each use. As with disposable needle electrode assemblies, reusable needle electrode assemblies are generally manufactured as a single unit having a needle electrode of a specified diameter and length, making it necessary for a physician to keep a large stock of various needle diameter and lengths on hand, adding to inventory and storage costs.
Some reusable needle electrode assemblies are designed with detachable needle electrodes. In such assemblies, an electrical housing and leads are formed as one unit and a needle electrode and an electrical connector used to connect the electrode to the leads are formed as a second unit.
It would be advantageous to have a needle electrode assembly that is reusable and does not require expensive and time-consuming sterilization procedures after each use. It would also be beneficial to have a needle electrode assembly that allows different sizes and lengths of needle electrodes to be releasably attached to electrical connectors and leads to reduce fabrication costs and allow physicians to stock various sizes and lengths of needle electrodes, as opposed to stocking various sizes of needle electrode assemblies.
The present invention is directed to reducing or eliminating some or all of the disadvantages of prior needle electrode assemblies discussed above.